C++ exception handling

The C++ exception handling mechanism allows programs to handle errors or unexpected conditions at runtime. It provides a structured way of catching and handling errors, making programs more robust and reliable.

Basic concepts of exception handling:

• Exception: An error or unexpected condition that occurs when a program is running.
• Throw an exception: Use throwthe keyword to pass the exception up the call stack.
• Catching exceptions: Use try-catchblocks to catch and handle exceptions.
• Exception type: An identifier representing the exception category.

Exception handling process:

1. Throw Exception: Use the keyword to throw an exception when an error or unexpected condition is detected throw.
2. Unstack: The exception propagates up the call stack until a matching catchblock is found.
3. CatchException: catchblock catches and handles thrown exceptions.
4. Exception handling: Within catcha block, you can execute code to handle exceptions, such as logging an error message, restoring program state, or terminating the program.

Example:

# include  <iostream>

int  main ()  {
   try {
     int age = 15 ;
     if (age < 18 ) {
       throw std:: runtime_error ( "Age must be 18 or older" );
    }
    std::cout << "Access granted - you are old enough." << std::endl;
  } catch ( const std::runtime_error& e) {
    std::cerr << "Error: " << e. what () << std::endl;
  }

  return  0 ;
}

In this example:

• throw std::runtime_error("Age must be 18 or older");statement will throw an std::runtime_errorexception of type if ageless than 18.
• catch (const std::runtime_error& e)The block catches std::runtime_errorexceptions of type and stores them in evariables.
• std::cerr << "Error: " << e.what() << std::endl;The statement will output exception information.

advantage:

• Improve program robustness: Exception handling enables programs to handle errors more gracefully and avoid program crashes.
• Improves code maintainability: Exception handling makes code easier to understand and maintain because it decouples error handling from normal code.
• Improved code reusability: Exception handling mechanisms can be easily integrated into existing code bases.

shortcoming:

• May cause performance degradation: Exception handling adds some runtime overhead because exceptions need to be checked and handled.
• May complicate code: Excessive exception handling may make code difficult to understand and maintain.

Summarize:

C++ exception handling is a powerful mechanism that can be used to improve the robustness, maintainability, and reusability of your programs. However, it is important to use exception handling with caution and avoid overusing it as it can lead to performance degradation and code complexity.

C++ Add two numbers

In C++, there are many ways to add two numbers. Here are some common methods:

1. Use basic operators

The simplest method is +to sum two numbers directly using the plus ( ) operator.

int num1 = 10 ;
 int num2 = 20 ;
 int sum = num1 + num2;

cout << "The sum of " << num1 << " and " << num2 << " is: " << sum << endl;

2. Use function

You can create your own function to add two numbers.

int  addNumbers ( int x, int y)  {
   return x + y;
}

int  main ()  {
   int num1 = 30 ;
   int num2 = 40 ;
   int sum = addNumbers (num1, num2);

  cout << "The sum of " << num1 << " and " << num2 << " is: " << sum << endl;
   return  0 ;
}

3. use class

You can create a class to encapsulate the sum operation.

class  Calculator {
 public :
   int  add ( int x, int y)  {
     return x + y;
  }
};

int  main ()  {
  Calculator calc;
  int num1 = 50 ;
   int num2 = 60 ;
   int sum = calc. add (num1, num2);

  cout << "The sum of " << num1 << " and " << num2 << " is: " << sum << endl;
   return  0 ;
}

4. Using STL functions

The C++ standard library provides std::plusfunctions for calculating the sum of two numbers.

# include  <iostream>
 # include  <functional>

int  main ()  {
   int num1 = 70 ;
   int num2 = 80 ;
   int sum = std:: plus < int >()(num1, num2);

  cout << "The sum of " << num1 << " and " << num2 << " is: " << sum << endl;
   return  0 ;
}

5. Using lambda expressions

You can use lambda expressions to create anonymous functions and perform summation operations.

# include  <iostream>

int  main ()  {
   int num1 = 90 ;
   int num2 = 100 ;
   int sum = []( int x, int y) { return x + y; }(num1, num2);

  cout << "The sum of " << num1 << " and " << num2 << " is: " << sum << endl;
   return  0 ;
}

These are just some of the ways to add two numbers in C++. Which method you choose depends on your specific needs and preferences.

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